Automatic shutter-tripper.



E. E. WEBSTER.

AUTOMATIC SHUTTER TRIPPER.

APPLICATION FILED DEC. 11. 1914.

Patented Mar. 21, 1916.

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H u k H U H u h V v r m k n v T. |Tll i. To all whom it may concernbanana n. wnes'rna, or CHICAGO, ILLINOIS.

AUTOMATIC SHUTTER-KEEPER.

Specification of Letters Batent. Patented Ma 21 1915,

Application filed December 11, 1914. Se'riaI No. 876,675.

Be it known that I, EDGAR E. WEBSTER, a

citizen of the United States, residing at Chi time interval so that theoperator, for 1nstance, may appear in the picture, or the device ofcourse is of use under other conditions where it would be advisable tohave the shutter automatically actuated after the elapse of a certaintime interval.

My device is primarily of use in connec- 1 tion with the shuttertrippers known as flexiification,

ble cable. release mechanism consisting of a flexible cable having afinger adapted mechanically to control the shutter mechanism so as tocause it to trip, thus to secure the exposure. My automatic mechanism tocontrol this release mechanically engages the free extremity of thisflexible cable release to actuate it as stated after the elapse of acertain time interval.

I will explain my invention more in detail by referring to theaccompanying drawlng illustrating two .embodiments thereof, in whichFigure 1 is a sectional view online e-a of Fig. 2 of my improved deviceshovfn in association with a flexible cable release; Fig. 2 is a view online b-b of Fig. 1 showing the device in its operated condition; Fig. 3is a top viewof the device shown in Figs 1 and 2; Fig. 4 is a sectionalview on line 0-0 of Fig. 2; Fig. 5 is a view similar to Fig. 1 on linedd of Fig. 6 showing a modand Fig. 6 is a sectional view on line ee ofFig. 5 showing the device in its operated condition.

My improved structure is designed to act upon a flexible cable releasemechanism 1' whose structure is well understood in the art and which atits extremity has a plunger 2 provided with a head 3 so arranged thatwhen this plunger is pushed inwardly toward the. cable 1, that a finger4 at the opposite extremity is forced outwardly to actuatethe shutter asis well understood. To clarlfy the flexible cable release mecha- .nismit's shown in its actuated condition 1n Flg. 2.

\My improved device has means for mechanically controlling the movementof the plunger 2 so that thls plunger" may be automatically actuated torelease the shutter after the elapse of a'certain timeinterval. Thestructure which I employ to accomplish this result includes a barrel orcylinder 5 having at its lower extremity a screw 6 adapted to control asmall opening or bleeder port s0 that the amount of air issuingtherefrom may be controlled to thereb control the speed with which thepiston 7 moves so as to permit adjustment or change vof the timeinterval. Thepiston 7 also has a barrel 8 which is slotted as shown at 9to permit a cross-piece 10 to remain in a given position irrespective ofthe movement of said piston. place by the screw threaded cap 11 andserves as the abutment for a spring '12, the opposite extremity of whichspring bears against the piston 7. The barrel when thus moved upwardlyinto the position of Fig. 1 compresses the spring 12 so that this sprlngtends to force the piston into the position of Fig. 2. A catch 13 pistonon the cap 11 may enter a notch 14 provided in the barrel 8 so as tohold this device in its set condition. Then when the time comes topermit the device to begin its actuations the catch 13 is released andthe spring 12 slowly forces the piston 7 into the position shown in Fig.2, the speed with which this is accomplished being dependent upon theamount of opening permitted by the screw '6. The barrel 8 at its upperextremity has a plurality of fingers 15, 15 and 16, 16, which areadapted to receive the flange 17 stationarily provided upon the cable 1.The barrel is also cut away as shown at 18 to form a bridge structureincluding these fingers 15 and 16 so that the plunger 2 and head 3 maybe inserted with the flange 17 held between these fingers, all as shownin Fig. 1. Assume then that the catch 13 is released, it will be evidentthat the spring 12 forces the piston downwardly and keeps on forcing thepiston downwardly until the head 3 engages the cross-piece 10, whereuponrelative movement between the elements 3 and 17 takes place, resultingfinally in a suficient This cross piece '10 is held in I movement of thepin 4: to trip the shutter. It will be readily understood that theelapsed time may be' controlled by the screw 6.

I have thus provided a mechanical structure capable of automaticallyoperating the flexible cable release mechanism.

In Figs. 5 and 6, I have shown a modified structure in which the piston7 carries a piston rod 19 encircled by the spring 12, the spring actingagainst the piston at one extremity and the cap 11 at the other.extremity. This piston rod carries at its upper extremity a fixedlymounted rectangular shaped bridge structure 20 having fingers 15 and 16to again hold the flange 17. lVithin this bridge structure is looselymounted a similar rectangular structure 21 which in the position shownin Fig. 5 is loosely slidable along the rod 19. It will be Seen thatwhen the spring 12 finally begins its actuation, the structure 21 firstengages the cap 11 and is then held in position against further movementdownwardly, while the structure 20 still continues its downward movementso that the upper loose portions of the structure 21 will engage thehead 3 and push it'inwardly, finally reaching the position shown in Fig.6 to cause a tripping of the shutter. The structure 21 has finger pieces22, 22 to permit pulling out the device into the position shown in Fig.5 so that the catch 13 may be set, whereupon the structure 21 ispermitted to drop into the position shown in Fig. 5 to permit of theflexible cable release mechanism bein inserted.

*rom What has been thus described the fiature of the invention will bereadily clear,

Having thus described various forms which my invention may take, what Iclaim as new and desire to secure by Letters Patent is:

A shutter tripper comprising mechanism for mechanically engaging andcontrolling the tripping device of a shutter, said mechanism includingclamping elements for en gaging the relatively movable extremities orone end of a flexible cable release mechanism, and slow acting means toautomatioally control said mechanism and actuate the same after theelapse of a predetermined time interval, said means including acylinder, .a piston, a piston rod, a spring for actuating said piston,said cylinder and piston forming a pneumatic chamber, meansforcontrolling the efiiux of fluid from said chamber, and a loosely mountedbridge piece carried by said piston rod forming I part of said clampingelements.

In witness whereof, I hereunto subscribe my name this third day ofDecember, A. D.

EDGAR E. WEBSTER. Witnesses .4

MAX W. ZABEL, HAZEL A. JONES.

